Application prospect of gallium nitride
What is gallium nitride?
Gallium nitride is a wide-bandgap composite semiconductor material. According to the 3rd party'' s estimation, after making use of GaN devices, the common mobile phone battery charger can reduce weight by as much as 40% or result more power under the very same dimension conditions. It relates to consumer, commercial, automotive, as well as various other electronic products. The target applications of this series include the built-in power supply of consumer electronic products, such as chargers, PC outside power adapters, LED lighting drivers, televisions, and various other home appliances.
Application possibility of gallium nitride
For GaN materials, the thickness of heteroepitaxial problems is rather high because the single substratum crystal has not been resolved for a lengthy time, but the tool degree has actually been useful. In 1994, Niya Chemical made 1200mcd LED; in 1995, it made Zcd blue light (450nmLED) as well as eco-friendly light 12cd (520nmLED); In 1998, Japan created a seven-year plan to create LEDs making use of vast band gap nitride materials. The objective is to create high-energy ultraviolet LEDs secured in fluorescent tubes as well as giving off white light by 2005. The power intake of this white LED is just 1/8 of that of incandescent lights and 1/2 of that of fluorescent lamps, as well as its life is 50-100 times that of standard fluorescent lamps. This proves that the growth of GaN materials has been quite effective and has actually entered the functional stage. The generation of InGaN system alloys, InGaN/AlGaN double joint LED, InGaN solitary quantum well LED, InGaN multiple quantum well LED, and so on have actually been created effectively. InGaNSQWLED6cd high-brightness pure eco-friendly tea as well as 2cd high-brightness blue LEDs have actually been produced. In the future, it can be accomplished by integrating with AlGaP and also AlGaAs series red LEDs to form a brilliant full-color display screen. This way, the white light resource blended with three main colors also opens up new application fields, and the period defined by high reliability and also long-life LED will certainly come. LEDs will certainly change fluorescent lights as well as light bulbs. LED will certainly end up being the leading product. GaN transistors will certainly develop quickly with product development as well as gadget innovation and also become a brand-new generation of high-temperature regularity as well as high-power tools.
Drawbacks and problems of gallium nitride
On the one hand, theoretically, because of its power band framework, the effective mass of the carrier is huge, as well as the transportation residential or commercial property is bad, so the low electric area flexibility is low, as well as the high-frequency performance is poor. On the various other hand, GaN single crystals grown by heteroepitaxy (using sapphire and SiC as substratums) are not really acceptable (which hinders the growth of GaN devices). For instance, the dislocation thickness reaches 108 ~ 1010/cm2 (although the crystal framework of sapphire as well as SiC resembles GaN, there are still fairly big lattice inequality and also thermal inequality); The background carrier (electron) concentration of undoped GaN at space temperature level is as high as 1017cm-3 (possibly pertaining to N openings, substitutional Si, substitutional O, etc), and reveals n-type conductivity; Although it is easy to attain n-type doping (doping Si can obtain n-type GaN with electron concentration of 1015 ~ 1020/cm3 as well as room temperature flexibility > 300 cm2/V. s), the p-type doping level is also low (mostly doped with Mg), the resulting hole concentration is only 1017 ~ 1018/cm3, movement